Blind stitch sewing machine



April 2, 1940. R. s. KELSO BLIND STITCH SEWING UACHINE 6 Sheets-Sheet 1 Filod Feb. 15, 1937 AP 'i 1940. i RS. KELSO 2,195,700

BLIND STITCH SEWING MACHINE Filed Feb. 15, 1957 s Sheets-Sheet 2 W/pdifeh MMW April 2, 1940. R. s. KELSO BLIND STITCH SEWING NACHI NE 6 Sheets-Sheet 3 Filed Feb. 15, 1937 R. s. KELSO 2,195,700

BLIND STITCH SEWING MACHINE Filed Feb. 15, 1937 6 Sheets-Sheet '4 R. s. KELSO BLIND STITCH SEWING MACHINE April 2, 1940.-

Filed Feb. 15, 1937 6 Sheets-Sheet s paaaipea-lm umrso s'rArEs PArs r OFFICE Application February 15, 1931, Serial No. 125,881

24 Claims.

This invention relates to new and useful improvements in blind stitch sewing machines generally, although more particularly to the stitch forming mechanism thereof.

" One of the principal objects of this invention is to provide a stitch forming mechanism for joining a hem to a body fabric by a line of 2- thread blind stitches wherein the needle thread loops overlie the inner edge of the hem to simjo ulate hand formed whip stitches and wherein the looper thread is concatenated with the needle loops to doubly lock the same and thereby avoid the accidental unraveling of the seam.

Another object of the invention lies in the provision of a stationary looper thread guide eye, which is located in such position with respect to thelooper movement so as to insure the looper loop being entered by the needle, and to effect the pull-ofi of the looper thread from the supply during the forward travel or needle loop entering movement of the looper.

A further object of the. invention resides in providing means for positioning the looper thread above 'the path of movement of the feed dog during the forwardend of its movement.

Another important object of this invention lies in the provision of means for oiling the driving eccentric pin of the looper motion whereby an increased speed of the machine can be maintained fora much longer period of time than heretofore obtained with machines having the same looper motion.

With these and other objects in view which will more fully appear, the nature of theinvention will be more clearly understood by following the description, the appended claims, and the several views illustrated in the accompanying drawings. v

In the drawings:

Figure 1 is a top plan view of a blind stitch sewing machine constructed in accordance with my invention,

Figure 2 is an enlargedleft end elevation of the forwardly extending arm and work support,

Figure 3 is a front elevation of the stitching head, a

Figure 4 is a perspective view of the presser foot, 4 Figure 5 is a plan view of the looper driving eccentric pin assembly,

' Figure 6 is a perspective view thereof,

Figure '7 is a sectional view of the assembly, Figure 8 is a section taken on the line 8-4 of F1 ure'l, 56 g ,(Cl. l12177) flgureQisaplanviewofthemainshaftand eccentric'pin connection, g 1

Figure 10 is a sectional view of the sleeve which surrounds the pin, v

Figure 11 is an end elevation of the pin show ing the oil reservoir thereon,

Figure 12 is an enlarged top plan view of a hem seam formed by my invention, 7

Figure I3 is a bottom plan view thereof, the body fabric being folded back to better expose '1 the stitching, a

Figure 14 is a sectional view taken on the line Il -ll of Figure 12, t

Figures 15 to 18 are enlarged plan views of the I presser foot and showing the stitch forming in- 16 strumentalities in their different positions during the formation of a stitch,

Figure 19 is a perspective view of the stitch forming parts as shown in Figure 17,

Figure 20 is a perspective view of the adjustable 'go looper thread guide, and

Figure 21 is a rear elevation showingthe driv-. l ing connections between themain shaft, and the top feed, the looper and the needle shaft.

Like reference. numerals designate corre'spond-' 2!! ing parts throughout the several figures of the drawingsa My invention is adapted especially for joining a hem B to a body fabric A by a line of blind stitches formed from a needle thread 0 and'a looper thread D, as shown in Figures 12, 13 and 14.

The needle thread C is formed into aseries of equally spaced and connected needle loops 5. These needle loops first enter and emerge from 35 the body fabric A or base layer at points 6 which are located below. the hem B, and then pass upwardly through the hem at points 1, the points 6 and 1 beinglocated in lines extending in parv allelism with the inner edge b of the hem, and 40 the loops being laid against the outer face of the hem in parallel planes diagonal to the general line of the hem with the bights 8 of the loops overlying the inner edge of the hem and with the connecting thread portions Sextending below 45 anchoring points 6. and the inner edge of the hem.

the connecting portions I 2 of the looper thread thus lying along the inner edge of the hem.

It will, therefore, be seen that each looper loop I passes through a needle loop I and around the neck of the next formed needle loop, or in other words each needle loop 5 is doubly locked by two looper loops' l0, one passing around the needle loop and-the other passing through the same.

Thus, I have produced a hem which is seamed by a line of 2-thread blind stitches wherein the bights'of the needle loops are disposed in planes diagonal to the general line of the hem to thereby simulate the ordinary hand made whip stitches, and wherein the needle loops are doubly locked by the looper thread to prevent the stitches from becoming accidentally unraveled.

My invention is shown as being applied to a sewing machine frame E which includes a base 13, a standard 14, and a horizontal arm I! which extends laterally from the upper end of the standard and terminates in a forwardly extending arm IS. A horizontal presser foot F is rigidly secured to the free end of the arm l6 and is provided with a longitudinal opening II. A main shaft I8 is joumaled in the arm vl5 and has one end extending across the rear end of the arm l6. An oscillatory needle shaft I9 is journaled in the arm l6 above the foot and is driven from the main shaft by the usual connections. A needle arm 20 which is fixed to the front end of the needle shaft carries a needle 2| which is threaded with the needle thread C and reciprocates across the opening ll of the foot. An upwardly spring pressed work support G is mounted on the base in front of the arm l5 and the left hand end 22 thereof projects under the foot F. A ridge forming disc 23 is mounted below the foot F for projecting nodes of the body fabric A and the edge b of the hem B upwardly through the presser foot opening I! into needle penetrating position. The disc 23 is fixed to a rock shaft 24 which is journaled on the under side of the work support G and is disposed in parallelism with the main shaft l8. Connections, indicated as a whole by the numeral 25, function to rock F to clamp the work against the thrust'of the needle, a portion of the clamp being located in rear of the disc 23 and below the opening I! of the foot. A 4-motion top feeding mechanism I which'is provided for feeding the work up to and past the needle, includes a feed dog 26 fixed to the forward end of a feed bar 21 which is provided intermediate its ends with a longitudinal slot 28 in which is located a pivot 29 supported on the right hand wall of the forwardly extending frame arm 16, the rear end of the feed bar having driving connections with an eccentric fixed to the projecting end of the main shaft IS. The feed dog 26 operates in the presser foot opening I! in rear of the disc 23 and cooperates with the work clamp H to feed the work. All of the above mechanism is well known in the art and a further detailed description is believed to be unnecessary.

A looper U which is threaded with the looper thread D cooperates with the needle 2| and with the feed to join the hem B to the body fabric A by the line of double-locked stitches shown in Figures 12, 13 and 14. The looper J is attached,

to the forward end of a looper rod 30 which extends longitudinally of the frame arm IS. The

looper rod 30 is fulcrumed on a ball stud 3| which is mounted on the lower end of a depending rock arm 32 pivoted on the right hand wall of the frame arm I 6. Attached to the rear end of the looper rod through the medium of a transverse pivot pin 33, is a transverse bearing sleeve 34 which engages around an eccentric pin 35 fixed to an angular arm 36 integral with the disc 31 fixed to theend of the main shaft l8, the longitudinal axis of the pin being inclined at substantially 45 to the longitudinal axis of the shaft. The sleeve 34 is retained on the pin 35 by a clamp 38 attached to the outer end of the pin. This looper motion, as applied to a single thread stitch forming mechanism, is well known in the art and is exemplified in the Dearborn Patent 639,669, December 19, 1899, the looper having six motions imparted thereto, namely, a forward movement, a transverse movement which is also a rocking movement, a backward movement, and a return transverse movement which is also a rocking movement. v Practice has demonstrated that machines equipped with this looper motion will not stand up under approximately 2800 R. P. M. owing to the eccentric pin becoming dry due to centrifugal action causing the oil to leave the pin at the inner end thereof. It will be noted that the outer end of the eccentric pin lies substantially in register with the longitudinal axis of the main shaft whereas the inner end of the pin is spaced from said axis, thus causing the oil to be drawn from the inner end of the pin to the outer end thereof from which it is discharged. Tests have shown that the eccentric will stick within 15 minutes when the machine speed has been increased to 3000 R. P. M.

I have provided means for oiling the inclined eccentric pin which, under actual tests, has functioned properly for several hours when the machine was running at a speed of 3200 R. P. M. To this end, the pin is provided intermediate its ends with a peripheral groove 39, and the sleeve is provided with a registering annular groove 40, the former containing a fibre wick 4|. mounted on the outer face of the sleeve 34 at the outer end thereof is an oil reservoir K which comprises a cup 42 having inner and outer end walls 43, 44, and a peripheral wall 45, and containing a fibre wick 46, the outer wall 44 being provided with filler openings 41. It will be noted that the longitudinal axis :rm of the main shaft I 8 intersects the transverse plane y-y of the reservoir K at the longitudinal axis zz of the eccentric pin 35. This is important because the centrifugal action of the pin on the reservoir is thereby reduced to a minimum. The reservoir K is in communication by means of a plurality of openings 48 formed in the sleeve with the interior bearing surface of said sleeve. The openings 48 thus supply lubricant to the plain internal hearing surface where it produces a. lubricating film which is slowly taken up by the oil grooves 49 formed in the bearing surfaces of the sleeve and redistributed over the bearing surfaces, while the lubricant flow tends to progress along the entire bearing owing to centrifugal action. Thus, by providing the sleeve with the oil reservoir, the eccentric pin will be lubricated properly for several hours while the machine is operating at high speed.

The looper J of my invention comprises a. shank 50 which is removably attached to the forward end of the looper rod 30, a looper beak 5| having an eye 52 for the looper thread D, and a spreader finger 53 having a side recess 54 in- Rigidly termediate its ends, the beak and the finger 53 being offset from the shank and spaced apart and projecting forwardly from the shank. The edge of the shank adjacent the beak 5| is provided with a longitudinally extending thread groove 55 which is in open communication at its rear end with a thread opening 56 formed in said shank, and the front end of the shank projects laterally beyond the beak 5| to form a stop shoulder 51.

Rigidly mounted on the presser foot F immediately in rear of the needle path of movement and in front of the top feed dog 26, is a bridge L which extends transversely across the opening I! in the foot. This bridge comprises a horizontal abutment 58 which is supported on the foot by legs 59, 60, the abutment being thereby disposed above the foot to provide a resultant space, and the left leg 60 being inclined upwardly andto the right from the foot to provide a cam surface for the looper thread D. Attached to the front of the foot is a hem guide GI, and supported'on the foot in front of the needle path is a downwardly spring-pressed retainer finger 62 having its free end projecting rearwardly for cooperation with the disc 23 to retain the fabric against forward movement when the disc is on its forward stroke of oscillation and also to retain the fabric against the thrust of the needle.

The needle thread C is first led through a tension device 53 mounted on the rear of the forwardly extending frame arm I6, thence through a guide eye 64 mounted on the front end of said arm, and thence to the needle.

The looper thread is first led through a tension device 65 mounted on the frame arm l6, thence through a guide eye 66 formed in the upper end of a vertical bracket arm 61 attached to the front end of the frame arm l6 by a screw 68, thence through a guide eye 69 formed in an ear Ill which extends forwardly from the lower end of said bracket arm 61, thence through a guide eye ll formed in the end of a horizontal arm 12 which is mounted on the lower end of the bracket arm 61 for lateral adjustments by a screw and slot connection I3, and thence to the thread eye 52 of the looper J, the guide eye 'II being lo cated above the looper J and at a point in-rear of the needle path and centrally between the ends of the rocking stroke of the looper.

In operation, a stitch forming cycle is illustrated in Figures to 19.

In Figure 15, the needle 2| is at the forward end of its stroke and has entered the body fabric A at the point 6 and has passed upwardly through the hem B at the point I. The needle loop 5 which extends through the needle eye includes a supply leg and a stitch leg. The looper J has not completed its rocking movement to the right hand side of the seam and neither has it completed its forward or needle loop penetrating movement.v The looper loop l0 which extends through the eye 52 of the looper includes a supply leg and a stitch leg. Both legs of the needle loop extend through the last formed looper loop in the seam at the left of the entering point 5. The looper loop extends around the needle loop between the needle shank and the entering point 6, the supply leg extending through the last formed needle loop which extends forwardly under the bridge L, and the stitch leg extending rearwardly through the last formed needle loop in the seam.

The needle, as shown in Figure 16, then begins its rearward stroke and bows upwardly the supply leg of the needle loop, and the looper con tinues its forward movement to project its own loop into the needle loop. It will be noted that the needle is substantially in a horizontal plane, and that both the beak 5| and the spreader finger 53 of the looper are in substantially a horizontal plane when the looper is moving into the needle loop. v

I The needle, as shown in Figures 17 and 19, then completes its rearward stroke, pulling thread from the supply and setting the previously formed stitch, and also shedding the needle loop onto the looper. The looper is rocked to the left hand side of the seam and is also moved forwardly into po-- sition wherein the looper loop, which is on the looper, will be subsequently entered by the needle. It will be noted that in this position of the looper the beak 5| and the spreader finger are in a substantially vertical plane, that the needle loop which is around the beak and finger lies against the stop shoulder 51 of the looper, that the legs of the looper loop diverge rearwardly from the looper eye 52, that the fed of the fabric takes place immediately following'the needle leaving the fabric and consequently if it were not for the retaining recess in the spreader finger, the feed would lessen the angle formed by the legs of the looper loop to such an extent that the.

needle on its next forward stroke would not with certainty enter the looper loop, and that the downwardly extending stitch leg of the looper loop is retained by the recess 54 in the spreader finger at such an angle whereby the needle will with certainty enter the looper loop.

The needle, as shown in Figure 18, then enters the looper loop and the looper moves rearwardly to shed the needle loop which was around the loop and thereby position said needle loop around the looper thread which extends from the looper eye 52 thence around the needle and, thence rearwardly under the bridge L to the last formed stitch. As the looper is rocked to the right hand side of the seam as shown in Figure 15, the looper thread which extends rearwardly from the looper eye and under the bridge L, will engage and cam along the left leg 59 and consequently the looper thread positioned between the inclined leg 59 and the looper eye 52 will be supported at a height suflicient to allow the top feed dog, which is moving forwardly, to pass thereunder.

The position of the looper thread guide eye II is very important because (1) it cooperates with the looper, during the rocking of the looper to the left, to take up slack in the looper thread and thereby insure the stitch leg of the looper loop being taut at the time the needle enters the looper loop, and (2) it cooperates with the looper during the forward movement thereof to pull sumcient looper thread from the supply for use in the next formed stitch.

It is of course to be understood that the details of structure and arrangement of parts may be variously changed and modified without departing from the spirit and scope of I claim: 1. A threadable looper comprising an attachmy invention.

ing shank having a beak and a spaced spreader nnger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, and the shank at its juncture with the beak forming a stop shoulder.

3. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, the beak being provided with a. thread groove in open communication with the beak eye and with the groove in the shank.

4. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, and the shank at its juncture with the beak forming a stop shoulder.

5. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one' end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, the beak being provided with a thread groove in open communication with the beak eye and with the groove in the shank, the shank at its juncture with the beak forming a stop shoulder.

6. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, and the spreader finger being provided intermediate its ends with a thread retaining recess.

'7. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, and the shank at its juncture with the beak forming a stop shoulder, and the spreader finger being provided intermediate its ends with a thread retaining recess.

8. A threadable looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, the beak being provided with a thread groove in open communication with the beak eye and with the groove in the shank, the shank at its juncture with the beak forming a stop shoulder, the spreader finger being provided intermediate its ends with a thread retaining recess.

9. In a blind stitch sewing machine, the combination with a horizontally reciprocatory threaded needle, of a threaded looper, means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardiy across the needle path whereby the looper in its forward movement will enter the needle thread loop on one side of the seam and whereby the looper will be then moved laterally to the other side of the seam into position for the looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper, and a spreader linger rigidly connected to the looper for COODBluiLiOIl therewith to retain the looper thread loop open for entrance by the needle.

10. In a blind stitch sewing machine, the combination with a horizontally, reciprocatory threaded needle, of a threaded looper, means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle path whereby the looper in its forward movement will enter the needle thread loop on one side of the seam and whereby the looper will be then moved laterally to the other side of the seam into position for the looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper, and a spreader finger rigidly connected to the looper for cooperation therewith toretain the looper thread loop open for entrance by the needle, said spreader finger being disposed in spaced relation to the looper and provided with a retaining recess intermediate its ends for one leg of said looper thread loop.

11. In a looper mechanism for sewing machines, the combination with a main shaft, of an inclined eccentric pin rigidly connected to one end thereof, a looper carrying rod, driving connection between the eccentric pin and the rod including a sleeve journaled on the p'in,-and an oil reservoir mounted on the outer end of the sleeve and having open communication with the periphery of the pin.' a

12. In a looper mechanism for sewing machines, the combination with a main shaft, of an inclined eccentric pin rigidly connected to one end thereof, a looper carrying rod, driving connections between the eccentric pin and the rod including a sleeve journaled on the pin, and an oil reservoir mounted on the outer end of the sleeve, the bearing surface of the sleeve being provided with a longitudinally extending groove, the sleeve being provided with at least one port in open communication with the reservoir and with the oil groove.

13. In a looper mechanism for sewing machines, the combination with a main shaft, of an inclined eccentric pin rigidly connected to one end of said shaft and having its longitudinal axis disposed at an angle of 45 to the longitudinal axis of the shaft, a looper carrying rod, driving connections between the eccentric pin and the rod including a sleeve journaled onthe pin, and an oil reservoir mounted on the outer end of the sleeve and having open communication with the periphery of the pin, the transverse plane of the reservoir intersecting the iongitudinal axes of said shaft and pin.

14. In a blind stitch sewing machine, the combination with a horizontally reciprocatory threaded needle, of a threaded looper, and means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle path whereby the looper in its 1 forward movement will enter the needle thread loop on one side of the seam and whereby the looper will be then moved laterally to the other side of the seam into position for the looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper.

15. In a blind stitch sewing machine. the combination with a horizontally reciprocatory threaded needle, of a threaded looper, and means for first moving the looper into the needle thread loop at one side of 'the seam being formed and then moving said looper laterally to the other side of said seam and into position for the looper thread loop to be entered by theneedle, then moving the looper rearwardly to shed the needle thread loop from the, looper, and finally moving said looper laterally to its initial position.

16. In a blind stitch forming mechanism for joining superposed fabrics, the combination of a presser foot having an opening, and astitch forming mechanism operating entirelyabove the foot and including a threaded needle mounted for reciprocations across the opening in thefoot, and a threaded looper cooperating with the needle and including a shank, a beak, and a spreader spaced from the beak, the beak being provided with a looper thread eye, the needle first entering the looper thread loop carried by the looper, then entering and emerging from the lower body fabric and then passing through the upper fabric, the looper first moving across the seam, then moving forwardly into the needle thread loop, and then moving back across the seam into position for the needle to enter the looper thread loop in front of the needle loop around the looper, said beak and spreader being disposed in a substantially horizontal plane when entering the needle loop and being disposed in a substantially vertical plane with the beak above the spreaderto position the looper thread loop in a substantially vertical plane for entrance by the needle.

1'7. In a blind stitch forming mechanism for joining superposed fabrics, the combination of a presser foot having an opening, and a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for reciprocations across the opening in the foot, and a threaded looper cooperating with the needle and including a shank, a beak, and a spreader spaced from the beak, the beak being provided with a looper thread eye, the needle first entering the looper thread loop carried by the looper, then entering and emerging from the lower body fabric and then passing through the upper fabric, the looper first moving across the seam, then moving forwardly into the needle thread loop, and then moving back across the seam into position for the needle to enter the looper thread loop in front of the needle loop around the looper, said beak and spreader being disposed in a substantially horizontal plane when entering the needle loop and being disposed in a substantially vertical plane with the beak above the spreader to position the looper thread loop in a substantially vertical plane for entrance by the needle, said spreader being provided with a recess intermediate its ends for retaining the stich leg of the looper thread in spaced relation to the needle thread loop around the looper.

18. In a blind stitch forming mechanism for joining superposed fabrics, the combination of a presser foot having an opening, a stitch forming mechanism operating entirely above the foot and including a threaded needle mounted for reciprocations across the opening in the foot, and a threaded looper cooperating with the needle and including a shank, a beak, and a spreader spaced from the beak, the beak being provided with a looper thread eye, the needle first entering the looper thread loop carried by the looper, then entering and emerging from the lower body fabric and then passing through the upper fabric, the

looper first moving across the seam, then moving forwardly into the needle thread loop, and then moving back across the seam into position for the needle to enter the looper thread loop-in front of the needle loop around the looper, said beak and spreader being disposed in a substantially horizontal plane when entering the needle loop and. being disposed in a substantially verti- Joining superposed fabrics, the combination of a presser foot having an opening, a stitch forming mechanism operating entirelyabove the foot and including a threaded needle mounted for reciprocations across the opening in the foot, and a threaded looper cooperating with the needle and including a shank, a beak, and a spreader spaced from the beak, the beak being provided with a looper thread eye, the needle first entering the looper thread loop carried by the looper, then entering and emerging from the lower body fabric and then passing through the upper fabric, the looper first moving across the seam, then moving forwardly into the needle thread loop, and then moving back across the seam into position for the needle to enter the looper thread loop in front of the needle loop around the looper, said tially horizontal plane when entering the needle loop and being disposed in a substantially vertical plane with the beak above the spreader to position the looper thread loop in a substantially vertical plane for entrance by the needle, a feeding mechanism including a 4-motion top feed dog foperating in the presser foot opening directly in rear of the needle path, and means for supporting the looper thread extending from the looper eye to the last formed stitch above the feed dog during the forward movement of the latter and while the looper is moving forwardly into the needle thread loop, said looper thread supporting means comprising a bridge mounted on the foot directly in rear of the needle path and extending across the opening thereof.

20. In a blind stitch sewing machine, the combination with a horizontally reciprocatory threaded needle, of a threaded looper, means formoving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle path whereby the looper in its forward ,movement will enter the needle thread loop on one side of the seam and whereby the looper will be then moved laterally to the other side of the seam into position for the-looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper, and a stationary looper thread guide located in rear of the needlepath and above the looper and centrally between the lateral positions of the looper.

- 21. In a blind stitch sewing machine, the combination with a horizontally. reciprocatory threaded needle, of a threaded looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with athread eye at the inner end of saidgroove, means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle path whereby the looper in its forward movement will enter the needle thread loop on one side of the seam and whereby the looper will be then moved laterally to the other side of the seam into position for the looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper, and a stationary'looper thread guide located in rear of the needle path and above the looper and centrally between the lateral positions of the looper.

22. In a blind stitch sewing machine, the combination with a horizontally reciprocatory threaded needle, of a threaded looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, the shank at its juncture with the beak forming a stop shoulder, means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle path whereby the looper in its forward movement will enter the needle thread loop on one side of the seam and whereby the'looper will be then moved laterally to the other side of the seam into position for the looper rear of the needle path and above the looper and 4 centrally between the lateral positions of the looper.

23. In a blind stitch sewing machine, the com-' bination with a horizontally reciprocatory threaded needle, of a threaded looper comprising an attaching shank having a beak and a spaced spreader finger extending longitudinally from one end thereof, the beak being provided with a thread eye adjacent its outer end, the shank adjacent the beak being formed with a longitudinally extending thread groove and with a thread eye at the inner end of said groove, the shank at its juncture with the beak forming a stop shoulder, the spreader finger being provided intermediate its ends with a thread retaining re- 'cess, means for moving the looper from one side of the seam being formed to the other side thereof and for moving said looper forwardly and rearwardly across the needle .path whereby the looper in, its forward movement .will enter the needle thread loop on one side of the seam and Y whereby the looper will be then moved laterally to the other side of the seam into position for the looper thread loop to be entered by the needle at a point in front of the needle thread loop on .the looper., and a stationary looper thread guide located in rear of the needle path and above the looper and centrally between the lateral positions of the looper.

24. In a blind stitch sewing machine, means for joining a hem to a body fabric by a line of stitches formed of needle and looper threads and simulating hand formed whip stitches overlying the inner edge of the hem, said means including a reciprocatory threaded needle, fabric feeding means, a looper having a mounting shank including a longitudinally extending beak provided with a thread eye adjacent its outer end and a spreader finger spaced therefrom, means for mounting said looper for cooperation with said needle wholly above the fabric whereby the line of stitches can be formed at varying distances from the edge limits of the fabric, and means for moving the looper in timed relation with said needle from one side of the line of stitches to the other and for moving said looper forwardly and rearwardly across the needle pathwhereby the looper in its forward movement will enter the needle thread loop on one side of the line of stitches and whereby the looper will then be moved laterally to the other side of the seam to spread a looper thread loop to be entered by the needle at a point in front of the needle thread loop on the looper.

I RALPH SIMPSON KELSO. 

